The Center for Disease Control (CDC) estimates the yearly incidence of mild Traumatic Brain Injury (mTBI) at approximately 1.2 million cases in the United States alone. Approximately 1/3 of these injuries occur in football. The Principal Objective of this NIH Phase II SBIR project is to develop and validate HitAlert", a low cost head impact alert system for monitoring mTBI for widespread use. Brain injury is difficult to "see", particularly on the field. What is lacking from the current state-of-the-art clinical techniques is the identification of the impact or series of impacts that triggers the clinical symptoms and changes in brain physiology that are indicative of concussion in the athlete. HitAlert provides the enabling technology that allows users at all playing levels to receive the highest level of care.